Chapter 14: Agriculture
The distribution of agricultural land in south and central
14.26: Infrared Photo of Agriculture Near Carberry
This large-scale image illustrates the usefulness of colour infrared photographs in the study of vegetation and agriculture. It shows clearly the influence of soil and drainage conditions on crop growth as well as the influence of farm practices on crops. The photo covers four complete quarter sections near Carberry as well as parts of quarter sections to the north, south, east, and west. To the south 1, west 2, and northwest 3 are areas of deciduous woodland—red with mottled texture and rounded shadows. Trees in the southeast are darker 4 and may be under some form of stress, possibly too little water. A light-toned gravel road 5 crosses the area from north to south and is joined by a gravel road from the east 6. Three groups of farm building can be seen 7, the two in the centre being protected by large north/south shelter belts 8 composed of deciduous trees, although a few coniferous trees are identifiable by their pointed shadows 9.
The mottled appearance of several fields 10 indicates that the area is underlain by sandy soils with variable water-retaining ability. Cropping is practised over much of the area with varying degrees of success. In this summer image most crops are at the mid-point of their growth cycle. For ease of identification letters are used to designate fields:
a) the outer part of this field has been cut, probably for hay.
b) this one shows variations in crop growth due to soil differences; higher dry areas support only a poor crop in areas that are yellowish in colour. In the northeast an area of darker red indicates a good crop with east/west rows 11.
The northeastern quarter section is divided into five north/south trending fields:
c) the major variation in crop growth results from soil differences; higher dryer areas particularly in the south support only a thin crop.
d) the bright red of this field indicates a healthy crop, but with poor patches (soil-related) in the north and south.
e) the dark green of this field is indicative of fallow.
f) the faint red colour indicates that there is a thin plant cover.
g) this field is similar to d); a healthy crop is growing with north/south rows and a few poorer patches in the centre.
The southeastern quarter section is divided into three north/south trending fields.
h) patches of poor growth in the south are soil-related, whereas in the centre and north pink flecks may result from the yellow blossoms of wild mustard that was missed during spraying operations
i) this field displays three variations.[i]; pink north/south rows with gaps between them; probably a row crop of corn that has not yet closed allowing reflection from the soil between the rows;[ii] yellow/green patches in the north, south and east resulting from soil variations, probably higher, dryer areas supporting a poorer crop; and [iii] bright red circular patches are weeds, probably Canada Thistle.
j) this field is similar to f). The red colour suggests a plant cover; also seen are lighter patches (higher, drier) and dark areas (lower, wetter).
The southwestern quarter section is divided into irregularly shaped fields, a function of topographic variations:
k) and l) are essentially the same, a faint red indicating a thin plant cover interrupted by many whitish patches of higher, drier land with poor plant growth.
m) this one exhibits the dark green indicative of fallow.
n) the northernmost field is mainly bright red, similar to d). The crop is growing better in the centre than to the east and west where soil deficiencies result in poor growth.
o) this is an irregularly shaped area between cropped fields, probably a belt that has been left in pasture.
Figure 14.26: Infrared Photo of Agriculture Near Carberry
Vertical colour infrared air photo by Prairie Agri Photo
Flight height: 7,200 feet a.s.l; lens focal length: 50 mm
Scale: 1:9,600 (approx.)
Location: Township 10; Range 15 WI
Map sheets: 1:250,000 62G Brandon
1:50,000 62G/14 Carberry
[i] Information from Jack McKinnon, Prairie Agri photo, Carman.
[ii] Information from Jack McKinnon, Prairie Agri photo, Carman.
[iii] Information from Jack McKinnon, Prairie Agri photo, Carman.